Needle-vibrating mechanism for sewing machines



June 8, 1943. s. ZONIS 2,321,447

NEEDLE-VIBRATING MECHANISMS FOR SEWING MACHINES Filed July 8, 1942 2 Sheets-Sheet 1 W LLMQM:

56 25 J5 MW June 8, 1943. s. ZONIS NEEDLE-VIBRATING MECHANISMS FOR SEWING MACH INES Filed July 8,

2 Sheets-Sheet 2 Patented June 8, 1943 UNITED STATES PATENT OFFICE I 2,321,447 NEEDLE-VIBRATING Mechanism FOR SEWING MACHINES Sydney Zonis, Bridgeport, CQIlHa, assignor to Thc Singer Manufacturing Company, Elizabeth,

N. 3., a corporation of New Jersey Application July 8 1942, Serial No. 450,104

'7 Claims.

This invention mates to improvements in sewiiig machines, and more particularly to improved mechanism for effecting a vibration of the needle laterally of its normal path of reciprocation.

The primary object of the present invention is the provision of a sturdy, compact needle-bar vibrating mechanism capable of being readily assembled within the head of the sewing machine.

With the above and other objects in View, as will hereinafter appear, the invention comprises the devices, combinations and arrangement of parts hereinafter set forth and illustrated in the accompanying drawings of a preferred embodiment of the invention, from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled in the art.

In the drawings which show the preferred embodiment of the invention- Fig. 1 represents a vertical sectional view taken longitudinal of a sewing machine head embody ing the invention.

Fig. 2 represents a horizontal sectional view taken substantially along the line 2-2. Fig. 1.

Fig. 3 is an end elevational view, partly in sec- Fig. is a perspective view of the improved vibratory needle-bar frame,- showing its preferred design.

Referring more in detail to the drawings, the invention is embodied in a sewing machine having a frame including a bracket-arm terminating in a head 2 overhanging a worl -s11pporting bed 3. Journaled for rotation in ball bearings, one of which is indicated as at 4 (Fig. l),- is a mainor arm-shaft 5 carrying at its outer end the usual belt-driven balance-wheel (not shown) and at its inner end a counterbalanced needlebar actuating crank 5. Fixed in the actuating crank 6 by means of a screw 7 is a crank-pin 8 having preferably io'urnaled thereon a needle-bearing 9, the outer race of which is snugly embraced by the upper end of a link Ill. The lower end of the link it? embraces a pin ll integral with a split collar. 52 clamped upon the usual needle-bar L3. Carried at the lower end of the needle-bar I3 is a suitable needle-clamp I 4 having mounted therein the usual threaded needle l5. Through the mechanism just described the needle 55 is reciprocated endwise to penetrate the fabric which is maintained in contact with the work-supporting base 3 by a presser-foot to (Fig. 3) carried on the lower end' of a spring-pressed presser-bar I'l journaled for endwise movement in a bushing l8 fixed in the machine head 2.

Complemental to the needle beneath the work-support 3 is a conventional form of looptaker (not shown) which cooperates with the needle in the production of stitches.

Referring now to the means utilized to vibrate the needle Hi; the needle-bar I3 is journaled in bearing bushings i 9, '20 provided in the vertically spaced arms 2|, 22} of a needle-bar-frame 23, the lower bearing bushing projecting through a clearance opening 2-3 in the bottom wall of the machine-head 2. Preferably formed integral with tl'ie needIe-ba-r-frame 23 adjacent its lower end is a supporting fulcrum-rod 24 jcurnaled at its opposite ends on opposed pintles 25 secured, by set-screws 2 6 (Fig.- 2), in spaced lugs 2? provided in the machine-head 2; The two pintles 25 are adapted to eiitend into suitable hardened socket-members ZS'mounted in the opposite ends of the needle-par-frame fulcrum-rod 24; the len'gth'of the fulcrum-rod preferably being" such that the pintles 25 are widely spaced andthereby rigidly Sustain the neediabar-frame 23 in its properly alined' position with the usual needleaperture in the throat-pate. To assist in supporting the needle-bar-frame 23 and to oppose Whatever sidewise thrust is imparted to the needle-bar l3, as a result of the offset position of the needle-bar actuating link it relative to the needle-bar 13 (Fig. 1); the needle-bar-frame 23 provided adjacent its upper end with a guide-lug 28 adapted to slide within a guidewa-y29 defined between the adjacent faces of a block 35 and" an angle-member 31. As shown in Fig.- 4; the block 30 is fastened for limited adjustinent in a direction parallel with the axes of the pintles 725 to the front wall of the machinehead 2, the block being preferably provided with a tongue '30 maintained seated. by a screw 32, in a slot '33 formed in the front wall of the machine head. The angle-member 3!. see 1v is se cured on the block 33 by a screw 34 passing through an elongated aperture 35 in the anglemember.

The needle-barfra me 23 is oscillated about the longitudinal axis of the fulcrum-rod 24 in timed relation with the usual lower feeding mechanism (not shown) by'means of connections comprisinga rock-lever 36 formed with a split lower end adapted to be clamped by a screw 31 on the ful crum-rod 24; The upper end of the rock-lever to is socketed to receive the tapered head 38 of a pivot-screw 39 threaded into the lower end of a pitman 43. A set-screw 4| (Fig. 2) is provided for locking the pivot-screw 33 in the pitman 49. At its upper end the pitman 40 is formed with a strap 42 embracing the outer race of a conventional needle-bearing 43 mounted upon an adjustable eccentric 44 secured on the arm-shaft adjacent the ball-bearing 4. It will be understood that as the arm-shaft 5 is rotated the eccentric 44 actuates the pitman 40 which in turn operates the rock-lever 36 to oscillate the needlebar-frame 23 about the axis of the supporting fulcrum-rod 24. The extent of oscillatory movement imparted to the needle-bar-frame is dependent upon the amount of eccentricity of the eccentric 44, and in order to vary the amplitude of the oscillatory movements of the needle-barframe to harmonize the same with the stitchlength to which the lower feeding mechanism is set, the eccentric 44 is constructed so that its eccentricity may be adjusted between certain limits. No detailed description of the constructive features of the adjustable eccentric 44 shown in the drawings will be given for the reason that the same is fully described in the U. S. patent to W. Myers, No. 2,128,031, dated August 23, 1938.

To effect adjustment of the eccentricity of the eccentric 44, the front wall of the machine-head 2 has mounted therein a detent 45 (Fig. 3), the details of construction of which are similar to those illustrated in the U. S. patent to W. Myers, No. 2,063,264, dated December 8, 1936. When it is desired to adjust the amplitude of oscillation of the needle-bar-frame 23, the detent 45 is manually depressed until the inner end 46 thereof enters a stop-notch 41 in the adjusting member 48 of the eccentric 44, after which, if desired, the detent can be turned and locked in depresssed position. With the adjusting-member 48 of the eccentric 44 thus latched against turning, partial rotation of the arm-shaft 5 will effect the desired adjustment of the eccentric 44. When the desired amplitude of oscillation of the needle-barframe 23 is obtained the detent 45 is manually shifted into retracted position.

The construction of the needle-bar-frame and its actuating connections are such that high speeds of operation, in the order of 4000 to 5000 stitches per minute, are readily attainable. To provide adequate lubrication for the bearing points requiring oiling, the machine-head 2 at its lower end is closed to provide an oil-sump 49 adapted to collect excess oil thrown oil by the rapidly rotating needle-bar crank 6 and eccentric 44. Projecting into the oil-sump 49 are a plurality of wicks 59 and 51 which conduct the oil collected in the sump 49 to the various bearing points. Wick 50, fastened to the arm 22 of the needle-bar-frame 23 by a securing screw 52' (Fig. 2), conducts the oil through a radial opening 53 in the needle-bar-frame fulcrum-rod 24 into a longitudinal bore 54 extending the full length of the fulcrum-rod 24. Disposed in the bore 54 and contacting the tapered extremities of the pintles 25 is a wick 55 which picks up oil from the end of the wick 50 and delivers it to the pintles 25. Also extending into the radial opening 53 and contacting the wicks 59 and 55 are a pair of wicks 56 and 51 (Figs. 1- and 2). The wick 56 is threaded through an inclined duct 58 in the needle-bar-frame 23, which duct opens into one of a pair of longitudinal grooves 59, 60 connected together at spaced points by ducts 6|. As observed in Fig. 1, the wick 56, after passing through the upper duct 6|, extends verticalli through a duct 62 and thence through a horizontal duct 53 which opens into the bearing surface of the needle-bar bushing l9 fixed in the upper arm 2| of the needle-bar-frame 23. To provide for lubricating the guide-lug 28 in the guide-way 29, the vertical duct 62 is intersected by a duct 34 of which the opposite ends thereof open into the parallel faces of the guide-lug 28'. From the above it will be understood that the wick 56 conducts oil absorbed from the wick or the wick upwardly lengthwise of the needle-barframe 23 to lubricate the upper needle-bar hearing and the guide-lug 23.

The wick 51 is threaded through a duct 65 provided in the lower arm 22 of the needle-barframe 23, which duct 65 opens into the bearing surface of the bushing 20, thereby conducting lubricant to the lower needle-bar bearing.

As shown in Figs. 1 and 2, the wick 5| is carried by the rock-lever 36 and is threaded through the longitudinal grooves 66 and, 61 which are connected together by the ducts 68. At its upper end the wick 5| bears against the tapered head of the pivot-stud 39 and thereby conducts oil to the bearing surface between the tapered head 38 of the stud and the upper end of the rock-lever 36.

It will be understood from the above description taken in connection with the accompanying drawings that there has been invented a needle-vibrating mechanism in which all the component parts thereof are compactly arranged within the machine-head and in such a manner as to provide a strong and sturdy mechanism capable of high speeds of operation. As previously described, the fulcrum-rod 24 is preferably integral with the needle-bar-frame 23, and, further, the fulcrum-rod is relatively long in order that the pintles supporting the needle-barframe can be widely spaced. One of the advantages obtained by supporting the needle-bar frame 23 on spaced pintles in a manner illustrated in the drawings is that the needle-bar I3 can be conveniently shifted in the direction of the axes of the pintles, thereby to aline the needle l5 with the usual needle-aperture in the throat-plate. The shifting of the needle-bar is readily accomplished by loosening the set-screws 26 and endwise shifting the two pintles 25 until the needle is in register with the needle-aperture in the throat-plate, after which the set-screws 26 are tightened to secure the pintles 25 in adjusted position. The split lower end of the rocklever 35 also facilitates in the adjusting of the needle-bar in the direction of the axes of the pintles. As a result of the adjustability of the needle-bar in the direction of the axes of the pintles, the degree of accuracy required when initially assembling the standard of the bracketarm casting upon the bed casting is reduced, thus facilitating the production of the machineframe. It will be appreciated that as a result of the relatively Wide space between the pintles 25 the efiect on the alinement position of the needle-bar-frame with respect to the needleaperture in the throat-plate of any play which may develop between the pintles and the socketmembers 28 after the mechanism has been in operation for some time will be minimized.

Having thus set forth the nature of the invention, What I claim herein is:

l. A sewing machine having a frame including a bracket-arm terminating in a head, an actuating shaft journaled in said bracket-arm and projecting into said head, a needle-bar. a

needle carried thereby, means including a crank mounted on that portion of said actuating shaft projecting into said head for endwise reciprocating said needle-bar, a needle-bar-frame disposed within said head and provided with at least one bearing in which said needle-bar is slidable, a pair of pintles fixed in said head, a fulcrum-rod supporting said needle-bar-frame and pivotally mounted on said pintles for oscillatory movement, an eccentric fast on said actuating shaft within the confines of said head, a rock-lever secured at its lower end upon said fulcrum-rod intermediate its ends, said rock-lever extending rearwardly and upwardly within said head, and a pitman connecting the upper end of said rocklever to said eccentric.

2. A sewing machine having a frame including a bracket-arm terminating in a head, an actuating shaft journaled in said bracket-arm and projecting into said head, a needle-bar, a needle carried thereby, means including a crank mounted on that portion of said actuating shaft projecting into said head for endwise reciprocating said needle-bar, a needle-bar-frame disposed within said head and provided with at least one bearing in which said needle-bar is slidable, a pair of pintles fixed in said head, a fulcrumrod provided at the lower end of said needle-barframe and pivotally mounted on said pintles for oscillatory movement, means for guiding the upper end of said needle-bar-frame, an eccentric fast on said actuating shaft within the confines of said head, a rock-lever secured at its lower end upon said fulcrum-rod intermediate its ends, said rock-lever extending rearwardly and upwardly within said head, and a pitman connecting the upper end of said rock-lever to said eccentric.

3. A sewing machine having a frame including a bracket-arm terminating in a head, an actuating shaft journaled in said bracket-arm and projecting into said head, a needle-bar, a needle carried thereby, means including a crank mounted on that portion of said actuating shaft projecting into said head for endwise reciprocating said needle-bar, a needle-bar-frame disposed within said head and provided with at least one bearing in which said needle-bar is slidable, a

pair of lugs provided within said head adjacent the lower end thereof, a pintle fixed in each of said lugs, a fulcrum-rod provided at the lower end of said needle-bar-frame and pivotally mounted on said pintles for oscillatory movement, guide means disposed at the upper end of said needle-bar-frame for confining said frame against movement parallel to the axes of said pintles, an eccentric fast on said actuating shaft within the confines of said head, a rock-lever secured at its lower end upon said fulcrum-rod, said rock-lever extending rearwardly and upwardly within said head, and a pitman connecting the upper end of said rock-lever to said eccentric.

4. Needle-vibrating mechanism for a sewing machine having a bracket-arm terminating in a head, comprising, a needle-bar-frame having a plurality of sockets, a needle-bar journaled in said frame for endwise reciprocation, means for reciprocating said needle-bar, means pivotally supporting said needle-bar-frame on said head with capacity for adjustment of said frame in a line longitudinally of said bracket-arm, said last named means including a pair of pintles fixed in said head and entering the sockets provided in said needle-bar-frame, and means for vibrating said frame on said pintles.

5. A sewing machine having a bracket-arm terminating in a head provided with a pair of spaced lugs, a needle-bar-frame, a fulcrum-rod provided on said needle-bar-frame, a needle-bar journaled in said frame for endwise reciprocation, means for reciprocating said needle-bar, means pivotally supporting said needle-barframe on said head with capacity for adjustment of said frame in a line longitudinally of said bracket-arm, said last named means including a pair of pintles fixed in said spaced lugs forwardly of the needle-bar and engaging the opposite ends of said fulcrum-rod, and means for vibrating said needle-bar-frame on said pintles.

6. A sewing machine having a bracket-arm terminating in a head provided with a pair of spaced lugs, a, needle-bar-frame, a needle-bar journaled in said frame for endwise reciprocation, means for reciprocating said needle-bar, means pivotally supporting said needle-barframe on said head with capacity for adjustment of said frame in a line longitudinally of said bracket-arm, said last named means including a pair of pintles fixed in said spaced lugs and engaging said needle-bar-frame, means for vibrating said frame on said pintles, a guide-way provided in said head, and a guide-lug on said needle-bar-frame slidable in said guide-way for confining the needle-bar-frame against movement parallel to the axes of said pintles.

'7. A sewing machine having a bracket-arm terminating in a head provided with a pair of spaced lugs, a needle-bar-frame formed adjacent one end with a fulcrum-rod and adjacent its other end with a guide-lug, a needle-bar journaled in said frame for endwise reciprocation, means for reciprocating said needle-bar, means pivotally supporting said needle-bar-frame on said head with capacity for adjustment in a line longitudinally of said bracket-arm, said last named means including a pair of pintles adjustably fixed in said spaced lugs and engaging the opposite ends of said fulcrum-rod, means for vibrating said needle-bar-frame on said pintles, and means on said machine cooperating with the guide-lug on said needle-bar-frame for confining the frame against movement in a line parallel to the axes of said pintles, said means comprising a guideway defined by a block secured to Isiidkhead and an angle member secured to said SYDNEY ZONIS. 

